Circuit interrupter



P 1950 A. VAN RYAN 2,521,194

CIRCUIT INTERRUPTER Filed June 6. 1947 4 Sheets-Sheet 1 INVENTOR ATTORNEY p 5, 1950 A. VAN IIRYAN 2,521,194

CIRCUIT INTERRUPTER Filed June 6. 1947 4 SheetsSheet 3 FIG. 4

NVENTOR jab k0; fin @412 BY I ATToPmEY Patented Sept. 5, 1950 ZQ EQU T .I E

l hisrinyention relates tocircuit interrupters and isan improvement over-the invention dis.- cl ed inmyconendins aop i om fi a 7 fi ed vJuly 19%, now Patent No.

1 4, in assignedtothe same assignee as this invention.

n neraL-this invention has the same object-s hose S t forth in my above noted copendin an li t on.

in my copending application, oyerrcenter toggle; link mechanism was employed sand-the cin- .cuit interrupter was aut m t l y t p e by b zeaking the toggle link mechanism. The presentinuention retains the toggle link mechanism butemnloyes a novel means of holding the toggle link m chanism extended, thoughnot 'QVBI'. center, t nder normal conditions, and .pr.ovides m ans for releasing the toggle link mechanism so 1441 it can colla se and allow automatic openin :1, cir uit interrupter.

Further objects of this invention are toproyide latch means for normally locking the toggle link mechanism in extended condition .and a1:- rangedto automatically release the-latch means to allow ,c olla-pseoftheioggle link-mechansm I and opening ,of the circuit interrupter ,on-overlq dthere y securing a moreprecise point at which the toggle link mechanism willsoollapse andrequ irin iess force for its release.

, embodiment of the invention shownin th acc mpanyin drawingsin which:

:Fl ll l 1 is a uertiaal sectional .viewpartly mli l aw y through .the circuit inter-rumor, suc vi w eorrespond-ing. to a section .onthe-li-ne 1-. J o Fi ure 3- ;Fig ur,e:;2 is a sectional view on the line 1- 2 of Figure l, suchyiew being partly brokenaway.

Figure ;3 is ,a yiew partlybroken away and pa tl in sec i n lookin .down on thenciricult interrupter In-this View the lower portionof l mechanism. has been omitted for .clearness.

F e 51 a iragrnentary sectional view, on the line, A ,ofsFi ure 1.

Figures a fra me tar v e partly insection and partly broken away showing the circuit nterru t op n position.

Figure 6 is a iragmentary wiewof aninter: mediate position that the parts take .du-ring automatic. pening of the circuit interrupter.

fil eu :7 is .a-iraementary iew showing the 119s on 9 1 parts ;Wh;i'1 the manipulating he, .1 :15 being move tow d manual openin no anasmentary view showing the .i can? Pehiswhenthe circuit interrupter has been opened.

5, Sept: 7, 194.8, for CircuitvBreakers and SouthMilwaukee z-wis as- Electric Company, a corpo- Beilerringto. theidrawings, it will be seen that theicircuit-interrupter-is mounted within a tank I or can l:.having ic1osed bottom and side walls terminating in'a' beaded upper edge indicated at 2. l the-tank is closed by means of a top or cover amnion-has a gasketiresting upon the beaded edge :2 .of the lower portion of the tank. The tank is provided with. abracket 5 of any suitable type, .whenebyit may beattached toa pole or othersupport in the usual manner. The top is held to'theta-nk by any suitable means, as by .means of the bolts 6 andnuts II Insulating bushings-8 extend downwardly into the tank and below the oil level as indicated and carry terrninals,-not shown, at their upper ends in accordance .with' theusual practice. The preferably lined :with a fiber lining 9.

' lheientire circuit interrupter is supported from era-bly proyided with sidewalls 1| :3 between which the bvable and stationary contacts are positioned. J'Bhestationary contacts are indicated by thereferenceoharacter and the movable contacts by-the reference character [5. The movable contacts/are. carried by metal .arms or levers' l5 which-are pivoted at l] and are provided with metalspacers IB against which the ends of a U.=sha-ped bronze ,or other metal conducting member l9 bears. The inner ends of the arms lfi iara slotted asindicated at 21! and receive the pin :21 v ,oar.ried by the insulating slide rod 22. When-the. switch is in closed position the parts are as shown inflig-ure 2. In order to open the switch, the slide sod is pulled'up'ward ly by means hereinafiter described and suddenly separates-the movable contacts from the stationaryeontacts and rocks the levers or arms is downwardly .into contact with the insulating bushings oir-spaoersls for the lower portion of theside-walls l3, and thus limits the upward travel-of theslide rod- 22 as well as'the down ward-rocking motion of --the movable contacts 55, see-Figured A-pair of tension springs :24 are connectedtoa transverse pin 25 at their lower ends and at their ,upper ends are anchored to the topi of the casing. .These springs, there fore, .constantlypuli upwardly .on the slide rod 22. The spin 2.5.seryes to pivot the lower arm 26 of a togglelink mechanism, the upper arm of such togglewlinkmeohanism heing mdioated at 21,-the arms being pivotally joined together as indicated tank is end of the arm 2! rigidly carries a pin 33 which is pivotally mounted in one of the arms 34 of a bell crank lever, the other arm of such bell crank lever being indicated by the reference. character 35.

It is to be noted that the pin 33 is diametrically I cut away at one end and the. remaining half of the pin bears against a shoulder 36 formed 4 tended. This automatic straightening out or restoring of the toggle link mechanism to its normal condition occurs while the movable and stationary contacts remain separated.

When the circuit interrupter is opened either by automatic or manual operation, the arm 43, see Figure 2, rocks downwardly into a displayed position. In resetting, the lineman engages the arm 43 with the switch stick and forces the arm upwardly, thus rocking the rock shaft 42 in a clockwise direction. The arm or lever 45 rigid with such rock shaft engages the under side'of the lever 35 and forces the lever 35 upwardly,

' -thus' depressing the arm 34 of the bell crank on a latch lever 37. The latch lever 37 is urged in a clockwise direction by means of the spring 33. It is provided with an extension or foot 39 at its lower end. The bell crank lever 34, 35 is provided with an upwardly projecting arm 40 which is connected to one end of a spring 4|, such spring being anchored at its other end to the cover 3, as shown in Figure l. The bellcrank lever is, therefore, urged in a counter-clockwise direction. It is loosely mounted on a rock shaft 42 journaled in any suitable manner in the cover 3 and projecting outwardly from one side of the cover and is provided with a manipulating eyeleted arm 43 adapted to receive a switch stick. Normally, this arm is housed in a downwardly opening casing 44 carried by the cover 3 and may be reached by the hook end of a switch stick so that the arm may be pulled downwardly to manually open the circuit interrupter or pushed upwardly to reset the circuit interrupter." A lever or arm 45is rigidly mounted'on the'rockshaft 42, see Figure l, and is connected by meansof a spring '45 with the arm 35 of lever heretofore described.

The spring 46' holds a footor extension-41 of the lever 45 in engagement with the under side of the arm 35 of the bell crank lever. :The lever or arm 45 is providedwith an extension 46 which, when the rock arm ormanipulating arm 43 is pulled downwardly, is adapted to en gage the foot 39 of the latch lever 31 and move such latch lever to the right as viewed in Figures 1 and 7 to disengage the pin 33 from the shoulder 36, and allows the springs 24 to raise the slide bar 22 and thus suddenly open the circuit interrupter.

On the other hand, provision has been made for the automatic opening of the circuit interrupter as by manipulating the extension 32 of the latch 29 so that on overload the latch '29 will be released and the toggle link mechanism will be allowed to collapse temporarily, thus allowing the springs 24 to suddenly open the switch. The toggle link will straighten itself out at the upper end of its stroke for it will beseen that the flattened face of the pin '33 will rock and will thus force the latch 3'! clear of the pin and allow the arm 34 of the bell crank lever to rock upwardly under the influence of the spring'4l'and will thus again straighten out the toggle link mechanism as upward motion of the lower end of the toggle link mechanism is prevented when the switch arms l6 strike the'spacers or stops 23, see Figure 5, in the manner hereinbefore described. Figure 6 shows the toggle link mechanism as it is collapsing and-Figure 8 shows the the bell crank toggle link mechanism straightened out or exlever' andmoving the circuit interrupter back into closed positon. Obviously, at any time during this closing motion, the automatic means hereinafter described can trip the latch 29 by engaging the extension 32 in the event overload still persists.

The condition responsive means or overload means for automatically tripping the circuit interrupter may take any desired form; for example a sol'enoidconsisting of a spool-like member" provided with an energizing winding 49 may be employed to draw a. magnetic plunger 50 upwardly into the cylindrical chamber 5|. It is preferable to provide an encircling yoke or frame 52 of magnetic material and to provide a downward extension 'or guiding sleeve 53, preferably of nonmagnetic material, for normally receiving the magnetic plunger 50, this sleeve being open at its bottom and a pin 54 being provided to dc termine the lower limit of the downward stroke of the magnetic plunger 50. The upper end of the magnetic plunger 50 is preferably tapered as indicated at 55 and a magnetic upper pole piece 56 located in the upper end of the chamber 5| is bored out or internally tapered corresponding to the upper tapered nose' 55 of the magnetic plunger 50. It is preferable to slot the lower end of the upper pole 56 and the upper end of the magnetic plunger to reduce eddy currents. A pin 51, preferably of nonmagnetic material,. extends through the upper pole 56 of the solenoid and is provided with a-small' collar 58 which is received in a cylindricalportion '59 in the upper pole 56. 1

The solenoid may be supported in any suitable manner from thelower assembly or insulating housing l2; for example, an insulating bracket 60 may be secured to the housing l2 and'may support the solenoid. An insulating trip member or lever. 6| is pivoted as indicated at 62 and its center of gravity is to the left of the pivot point so that it tends to remain in the position shown in Figure 1 under normalconditions. This trip member 6| is adapted to be rocked in a clockwise direction on overload when the pin 51 is moved upwardly in a manner hereinafter described. Clockwise motion of the trip member 6| or lever causes it to engage the extension 32 of the latch 29 and to thus release the latch and allow automatic opening of the circuit interrupter to occur. 1

Assume that a heavy'overload occurs. Under these conditions the magnetic plunger 50 starts upwardly suddenly and places the oil in the cylindrical chamber 5| under very heavy pressure, it being understood that the entire solenoid is submerged in the oil contained in the casing as indicated in Figure'l. This heavy pressure drives the pin 51 upwardly and rocks the trip member GI and thus causes automatic opening of the circuit interrupter, On the other hand, suppose that an overload occurs just sufficient to cause upward travel of the plunger 50. Upward travel of the plunger 59 is delayed due to the time delay action of the oil in the cylindrical chamber 5 l. The displaced oil has to leak around the plunger or armature 50 as the armature moves upwardly and consequently a time delay is provided. As the air gap is shortened between the upper end of the plunger 59 and the upper pole piece 56, the pull on the plunger increases very greatly and the oil pressure above the plunger correspondingly increases. This oil pressure is sufiicient under all but the very lightest overloads to at least finally move the trip pin 57 upwardly and cause automatic opening of the circuit interrupter. On extremely small overloads the upper end of the plunger 59 actually engages the pin 5'! and causes automatic opening of the circuit interrupter.

It is to be noted that the cylindrical portion 59 is closed at its upper end by the insulating bracket 96 except for the difference in diameter between the pin 51 and the hole through which it extends. The purpose of this construction is to have the collar 58 and the cylinder 59 form a shock absorbing hydraulic means so that high currents of short duration, such as caused by lightning surges, will not trip the circuit interrupter. A short time delay is thus provided for the pin 51 so that high current values will have to be maintained for a short time before a trip action can occur.

It will be seen that this invention provides a novel form of circuit interrupter in which a very small amount of force is required to operate the latch and allow automatic collapse of the toggle link mechanism. The point at which tripping I occurs is precisely determined by the latch.

Further it will be seen that after collapse of the toggle link mechanism it is automatically again straightened out and ready to be moved downwardly when the circuit interrupter is manually reset as described hereinabove,

It will be seen that the mechanism of the circuit interrupter is simple and reliable in its operation and positively determines the exact point in the motion of the parts at which tripping will occur.

Although this invention has been described in considerable detail, it is to be understood that such description is intended as illustrative rather than limiting, as the invention may be variously embodied and is to be interpreted as claimed.

I claim:

1. A circuit interrupter comprising stationary and movable contact means, means biasing said movable contact means away from said stationary contact means, toggle link mechanism arranged when extended to hold said movable contact means in engagement with said stationary contact means, a latch for locking said toggle link mechanism in extended condition, condition responsive means for tripping said latch to allow collapse of said toggle link mechanism, reset means for closing said circuit interrupter, and automatic means arranged to extend said toggle link mechanism after collapse thereof without closing said circuit interrupter, said automatic means being independent of said reset means.

2. A circuit interrupter comprising stationary and movable contact means, means biasing said movable contact means away from said stationary contact means, toggle link mechanism arranged when extended to hold said movable contact means in engagement with said stationary contact means, a latch pivoted on one arm of said toggle link mechanism for locking said toggle link mechanism in extended condition before said toggle link mechanism has passed dead center, reset means for closing said circuit interrupter, condition responsive means for tripping said latch to allow collapse of said toggle link mechanism, and means independent of said reset means for extending said toggle link mechanism after collapse thereof.

3. A circuit interrupter comprising switch means, normally extended toggle link mechanism having a first arm and a second arm, said second arm having its outer end connected to said switch means, holding means normally holding the outer end of said first arm against motion of transla tion, means biasing said switch means towards opening motion and biasing said toggle link meche anism towards motion of translation, a latch carried by one arm of said toggle link mechanism for holding said toggle link mechanism extended when said toggle link mechanism is close to dead center but before said toggle link mechanism has passed dead center, condition responsive means for tripping said latch to allow collapse of said toggle link mechanism and opening of said switch means, and means for releasing said holding means to cause opening of said switch means without collapse of said toggle link mechanism.

4. A circuit interrupter comprising switch means, normally extended toggle link mechanism having a first arm and a second arm, said second arm having its outer end connected to said switch means, a first latch normally holding the outer end of said first arm against motion of translation, means biasing said switch means towards opening motion and biasing said toggle link mechanism towards motion of translation, a second latch carried by one arm of said toggle link mechanism for holding said toggle link mechanism extended, condition responsive means for tripping said second latch to allow collapse of said toggle link mechanism and opening of said switch means, means arranged to detach said first latch from said first arm upon collapse of said toggle link mechanism, means for automatically extending said toggle link mechanism after detachment from said first latch, and manually operable means movable in one direction to detach said toggle link mechanism from said first latch to open said switch means and movable in the other direction to close said switch means and cause re-engagement of said toggle link mechanism and said first latch.

ANTHONY VAN RYAN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 917,542 Cheney Apr. 6, 1909 2,162,534 Klein et a1 June 13, 1939 2,298,143 May Oct. 6, 1942 2,312,753 Coy Mar. 2, 1943 2,357,959 Kouyoumjian Sept. 12, 1944 2,425,770 Walle Aug. 19, 1947 

